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BaZrO _3 and KTaO _3 are two rare examples of perovskite oxides that retain the ideal cubic structure down to the lowest temperature. In this paper, we report thermal conductivity ( κ ) between 300 and 773 K on single crystals of these compounds. For BaZrO _3 , the κ of 7.5 Wm ^−1 K ^−1 at 300 K is ∼40% larger than the previously reported polycrystalline values. For KTaO _3 , our value of 13.1 Wm ^−1 K ^−1 at 300 K clarifies the sources of error in some of the previously reported data. These results underscore the importance of high-quality experimental data in benchmarking the accuracy of advanced first-principles κ calculations.

The interplay between charges and spins may influence the dynamics of the carriers and determine their thermoelectric properties. In that respect, magneto-thermoelectric power MTEP, i.e. the measurements of the Seebeck coefficient S under the application of an external magnetic field, is a powerful technique to reveal the role of magnetic moments on S. This is illustrated by different transition metal chalcogenides: CuCrTiS4 and CuMnTiS4 magnetic thiospinels, which are compared with magnetic oxides, Curie-Weiss (CW) paramagnetic misfit cobaltites, ruthenates, either ferromagnetic perovskite or Pauli paramagnet quadruple perovskites, and CuGa1-xMnxTe2 chalcopyrite telluride and Bi1.99Cr0.01Te3 in which diluted magnetism is induced by 3%-Mn and 1%-Cr substitution, respectively. In the case of a ferromagnet (below TC) and CW paramagnetic materials, the increase of magnetization at low T when a magnetic field is applied is accompanied by a decrease of the entropy of the carriers and hence $$\left| S\right|$$ decreases. This is consistent with the lack of MTEP in the Pauli paramagnetic quadruple perovskites. Also, no significant MTEP is observed in CuGa1-xMnxTe2 and Bi1.99Cr0.01Te3, for which Kondo-type interaction between magnetic moments and carriers prevails. In contrast, spin glass CuCrTiS4 exhibits negative MTEP like in ferromagnetic ruthenates and paramagnetic misfit cobaltites. This investigation of some chalcogenides and oxides provides key ingredients to select magnetic materials for which S benefits from spin entropy.

A novel heterogeneous catalytic nanomaterial based on a molybdenum cluster-based halide (MC) and a single-layered copper hydroxynitrate (CHN) was first prepared by colloidal processing under ambient conditions. The results of the elemental composition and crystalline pattern indicated that CHN was comprehensively synthesized with the support of the MC compound. The absorbing characteristic in the ultraviolet and near-infrared regions was promoted by both of the ingredients. The proper chemical interaction between the materials is a crucial reason to modify the structure of the MCs and only a small decrease in the magnetic susceptibility of CHN. The heterogeneous catalytic activity of the obtained MC@CHN material was found to have a high efficiency and excellent reuse when it is activated by hydrogen peroxide (H2O2) for the degrading reaction of the organic pollutant at room temperature. A reasonable catalytic mechanism was proposed to explain the distinct role of the copper compound, Mo6 compound, and H2O2 in the production of the radical hydroxyl ion. This novel nanomaterial will be an environmentally promising candidate for dye removal.